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<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <script>
        function Student(name,age){
        this.name=name;
        this.age=age;
    } 
    Student.prototype.say=function(){
        alert('this is say');
    }
    var stu1=new Student('lisi',20);  
    var stu1=new Student('zhangsan',25);
    stu1.say();
    stu2.say();
    console.log(stu1.say==stu2.say);
    </script>
</head>
<body>
    
</body>
</html>